摘要:
TDMA has wide application in tactical data links in virtue of its good anti?interception, anti?jamming and flexible networking capabilities.Each slot’s pulses can be divided into coarse synchronization,fine synchronization,header and message.By analyzing TDMA system structure and slot structure,the inherent frequency hopping pattern in thirty?two coarse synchronization pulses in timeslot structure.Based on simulation analysis,a timeslot header extraction method is put forward based on the frequency hopping pattern.This method is simulated and tested in the case of pulse lost.The simulation results show that this method is available and can lay a foundation for sequent timeslot analysis.%戰(zhàn)術(shù)數(shù)據(jù)鏈中,時(shí)分多址接入( Time Division Multiple Access , TDMA )技術(shù)具有良好的抗截獲和抗干擾能力,組網(wǎng)靈活,因此得到廣泛應(yīng)用。針對(duì)偵察TDMA系統(tǒng)時(shí)需要確定時(shí)隙頭位置(即時(shí)隙首脈沖到達(dá)時(shí)間)的問題,在對(duì)TDMA系統(tǒng)結(jié)構(gòu)和時(shí)隙結(jié)構(gòu)進(jìn)行分析的基礎(chǔ)上,研究時(shí)隙結(jié)構(gòu)中粗同步部分32個(gè)脈沖存在的固有跳頻規(guī)律,通過仿真分析提出了基于該跳頻規(guī)律的時(shí)隙頭提取方法,在脈沖丟失概率較高的情況下對(duì)該方法進(jìn)行了蒙特卡羅仿真測(cè)試,仿真結(jié)果驗(yàn)證了算法的有效性,從而為后續(xù)的時(shí)隙分析奠定基礎(chǔ)。
摘要:
在跳頻通信系統(tǒng)中,跳頻圖案生成大多基于FPGA實(shí)現(xiàn)。提出了一種新的基于DSP生成跳頻圖案的方法。分析了DSP/BIOS的啟動(dòng)過程和DSP定時(shí)器工作原理,通過對(duì)DSP定時(shí)器計(jì)數(shù)器的控制,利用定時(shí)器中斷生成跳頻周期,進(jìn)而生成跳頻圖案。對(duì)方法的實(shí)現(xiàn)結(jié)果進(jìn)行了測(cè)試,給出了分別采用CLK和PRD模塊實(shí)現(xiàn)時(shí)的跳頻周期曲線,分析了測(cè)試結(jié)果,指出采用CLK模塊更有優(yōu)勢(shì),可以滿足系統(tǒng)設(shè)計(jì)需求。%In the implementation of frequency hopping system, frequency hopping pattern is usu-ally generated based on FPGA. A new frequency hopping pattern generation method is proposed here, based on DSP. The startup procedure of DSP/BIOS is analyzed at first, then the working principle of the DSP timer is too. Through the control of DSP timer counter, the frequency hopping period is generated using the timer interrupt. So the frequency hopping pattern is gener-ated. The results of this method are tested and given, including the frequency hopping period curves separately using DSP/BIOS’ s CLK and PRD modules. With the analysis of the results, it is pointed out that CLK module is better over PRD module in the frequency hopping pattern gen-eration. The method can meet the system design requirements.
摘要:
基于MATLAB平臺(tái)研究跳頻擴(kuò)頻調(diào)制器的實(shí)現(xiàn),給出了跳頻擴(kuò)頻調(diào)制的原理,利用simulink模塊實(shí)現(xiàn)跳頻擴(kuò)頻調(diào)制。選擇15位的擴(kuò)頻碼進(jìn)行擴(kuò)頻,跳頻圖案也采用15位的m序列產(chǎn)生。經(jīng)過仿真,觀察仿真結(jié)果,該模型能夠?qū)崿F(xiàn)跳頻擴(kuò)頻調(diào)制,跳頻頻點(diǎn)數(shù)15個(gè),跳頻速率為0.04s/跳。%This paper studies the realization of the frequency hopping spread spectrum modulator based on MATLAB platform and provides the principle of frequency hopping spread spectrum modulation. Then the simulink module is used to realize the frequency hopping spread spectrum modulation. The length of spread spectrum code in spread spectrum is 15 and frequency hopping pattern is also obtained by m sequence with length of 15. Through the simulation, the author observes the simulation results. This model can realize frequency hopping spread spectrum modulation. Jump points are 15 and frequency hopping rate is 0.04 s per jump.